1. Field of the Invention
The present invention relates to the field of information handling system chassis, and more particularly to a system and method for electrical communication through a non-conductive information handling system chassis surface.
2. Description of the Related Art
As the value and use of information continues to increase, individuals and businesses seek additional ways to process and store information. One option available to users is information handling systems. An information handling system generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes thereby allowing users to take advantage of the value of the information. Because technology and information handling needs and requirements vary between different users or applications, information handling systems may also vary regarding what information is handled, how the information is handled, how much information is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated. The variations in information handling systems allow for information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, information handling systems may include a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more computer systems, data storage systems, and networking systems.
Information handling systems are typically built from a variety of components provided by a variety of suppliers. Generally the components are built into a chassis which serves the dual purpose of protecting the components in a solid structure and providing shielding of electromagnetic radiation produced by the components. For example, a metallic chassis provides support against physical damage that might occur to components if the chassis is dropped or bumped. A metallic chassis also creates a Faraday cage to provide effective containment of electromagnetic radiation generated within the chassis. Often, an information handling system chassis is built from a number of metallic parts that are assembled during the manufacture process. When multiple metallic parts are used to build the chassis, the separate pieces are typically electrically connected with each other in order to provide electromagnetic shielding by the assembled parts. For example, metal grounding clips are connected between different chassis parts so that electrical energy flows between the surfaces of each chassis part.
Information handling system chassis are built from a variety of metals and alloys. One metal that has gained acceptance for use in information handling system chassis is magnesium. Magnesium offers light weight and a hard surface that resists scratches and other damage, qualities that are desirable in portable information handling systems. One disadvantage with magnesium is that it tends to oxidize rapidly. To address oxidation, magnesium chassis components are typically treated prior to painting. Generally, heavy metal passivation techniques have been abandoned in favor of more environmentally friendly techniques, such as phosphate passivation treatment. However, conventional passivation treatment techniques tend to reduce the conductive properties along the surface of the magnesium. For example, one type of passivized magnesium has resistance of approximately 410 Milliohm while unpassivized magnesium has resistance of approximately 5.3 Milliohms. In order to provide effective electromagnetic suppression, a chassis surface should have resistance of less than 30 Milliohms. Although magnesium surface conductivity may be increased by other techniques, such as chromium pickling, plating and spray-on conductive coatings, such techniques tend to be costly and environmentally unfriendly both in the application of the materials at manufacture and the recycling of materials at end of use. Conductive gaskets typically have little success establishing electrical communication with a magnesium chassis. Conductive clips typically need substantial physical force to establish electrical communication and, once established, expose the magnesium surface to oxidation.